package ink.ykb.web;

import java.security.MessageDigest;

/**
* SHA1 摘要算法工具类
*
*/
public class WebTokenSHA1Util {

	
	 public static String getSha1(String str) {
	        if (str == null || str.length() == 0) {
	            return null;
	        }
	        char hexDigits[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
	        try {
	            MessageDigest mdTemp = MessageDigest.getInstance("SHA1");
	            mdTemp.update(str.getBytes("UTF-8"));

	            byte[] md = mdTemp.digest();
	            int j = md.length;
	            char buf[] = new char[j * 2];
	            int k = 0;
	            for (int i = 0; i < j; i++) {
	                byte byte0 = md[i];
	                buf[k++] = hexDigits[byte0 >>> 4 & 0xf];
	                buf[k++] = hexDigits[byte0 & 0xf];
	            }
	            return new String(buf);
	        } catch (Exception e) {
	            return null;
	        }
	    }
}
